Blocking of the vertical acid mist suction channel due to scaling such as copper sulfate scaling at the upwards facing inlet opening is a problem. This can hinder the acid mist flow, which results in increased acid mist in the tankhouse space atmosphere causing increased worker health risk and also equipment corrosion.
Various methods and arrangements for collecting and removal of acid mist from an electrolytic cell in metal electrowinning process or a metal electrorefining process are known in the art.
Publication US 2011/0108414 presents a multi-element cover system for controlling acid mist in metal electrowinning or electrorefining cells is made of an electrolyte resistant material and is applied above the surface of the electrolyte and below the electrical connections of the electrodes in order to provide a continuous and substantially airtight seal above the electrolyte. The cover system comprises a plurality of flexible longitudinally concave caps arranged between the cathode and the anode that help to shift the acid mist towards the sides of the cell using the same energy that disengages it from the electrolyte; lids between the electrodes and the wall of the corresponding end of the cell; and lateral enclosures located at both sides of the cell in the space between the electrodes and the lateral walls of the cell, the lateral enclosures having at least a top side, end walls at each end and an inner side projecting towards the electrolyte, thus forming a chamber inside the lateral enclosure, with the lower side of the enclosure or the electrolyte itself acting as the bottom boundary of the chamber, the chamber being connected to external acid mist suction means and its inner side provided with bores above the electrolyte level so as to in this fashion, in collaboration with the flexible caps, uniformly suck and remove the acid mist confined under the caps throughout the entire cell with a gentle suction and without the risk of crystal formation due to oversaturation of the droplets contained in the mist.